Coupling for flexible drive cables for sewer cleaners and the like



Nov. 22, 1960 P. 1.. clAcclo 2,950,851

COUPLING FOR FLEXIBLE DRIVE CABLES FOR SEWER CLEANERS AND THE LIKE Flled May 25 1959 Zia INVENTOR.

PE TEA L. tmcco A'rrox viy United States Patent COUPLING FOR FLEXIBLE DRIVE CABLES FOR SEWER CLEANERS AND THE LIKE Peter L. Ciaccio, 9059 Venice Blvd., Los Angeles, Calif.

Filed May 25, 1959, Ser. No. 815,639

8 Claims. (Cl. 64-6) This invention relates to flexible drive cables of tubular, closed coil helically coiled spring wire construction Sometimes referred to as coil-rod, utilized in driving various rotary cleaning tools such as are employed with heavy duty industrial type apparatus for cleaning sewer lines (e.g. in the operations of municipal street and highway maintenance departments). Such drive cables, in the smaller sizes for the cleaning of plumbing lines in houses are commonly referred to as snakes. In the larger in dustrial sizes, they are utilized in sections which are coupled to one another to provide a line of drive cable which may extend several blocks in a sewer line.

In the use of the heavy duty flexible drive cables in sewer cleaning operations, it is customary to feed them into the sewer by means of a motor driven feeding apparatus having a pair of feed rolls between which the drive cable is engaged, one of these rolls having concave helical serrations which mate with the helical turns of wire of which the drive cable is composed, whereby this feed roll is geared to the drive cable for effectively moving it longitudinally. In the normal operation of such an apparatus, when one of the coupling joints between consecutive sections of the drive cable meets the feed rolls, the rolls must be spread apart to allow passage therebetween of the coupling union, and the driving connection between the feed rolls and the drive cable is thereby broken. It is usually necessary for the attendant operator to grasp the drive cable in his hands and manually pull it forwardly until the coupling joint has passed beyond the feed rolls and the latter can again establish geared engagement with the drive cable.

The present invention deals with this problem, and has as its general object to provide an improved joint in a sectional flexible drive cable of a character such that the joint will pass between a pair of feed rolls without breaking the geared connection between the rolls and the drive rod.

More specifically, the invention contemplates a drive cable coupling embodying male and female threaded coupling parts, the latter being a nut having a periphery that is helically ribbed to provide a continuation of the helical turns of the drive cable itself, whereby the nut will pass between the feed rollers.

Other objects and advantages will become apparent in the ensuing specifications and appended drawings in which: 1

Fig. 1 is a perspective view of a flexible drive cable rjoint embodying the invention, shown in connection with the feed rolls of a sewer cleaning apparatus;

Fig. 2 is a view partially in side elevation and partially 2,950,851 Patented Nov. 22, 1960 broken away and in axial section, showing the details of the joint;

Fig. 3 is a transverse sectional view of the same taken on the line 3-3 of Fig. 2;

Fig. 4 is a detail sectional view of the coupling unit;

Fig. 5 is an end view of one of the coupling parts;

Fig. 6 is a view, partially in side elevation of a modified form of the invention;

Fig. 7 is a transverse sectional view thereof, taken on line 7-7 of Fig. 6; and

Fig. 8 is a fragmentary side view of one of the modified coupling parts.

Referring now to the drawings in detail, I have shown therein, as an example of one form in which the invention may be embodied, a coupling for joining the ends of flexible drive cable sections 10 and 11, said coupling comprising, in general, a pair of coupling parts 12 and 13 adapted to be anchored in the ends of the respective drive cable sections 10 and 11, and a union nut 14 for coupling the parts 12 and 13 to one another.

The coupling part 12 embodies a shank 15 having a male thread 16 of a form such as to eflect threaded meshing engagement with the internal walls of the turns of the respective drive cable section 10, a neck 17 having a conventional male thread 18 for threaded coupling with the nut 14, and an intermediate flange 19 adapted to seat against the end of the drive cable section 10. In the end of neck 17 is a diametral jaw clutch slot 20 of rectangular cross section, defined between a pair of clutch jaws 21.

The coupling part 13 embodies a threaded shank or stem 22 having a male thread corresponding to the thread 16 of shank 15 and adapted to be anchored in the end of the adjoining drive cable section 11 by threaded engagement with the internal walls of the turns thereof. On its other end, coupling part 13 has a cylindrical head 23 and a diametrically positioned clutch jaw 24 of rectangular section for reception in the clutch slot 20 of coupling part 12 and for clutching engagement with the jaws 21 thereof. The head 23 is receivable within the nut 14, which has a radially inwardly extending flange 25 defining a circular opening through which the stem 22 is adapted to project. Flange 25 is engageable against the back side of head 23 to clamp the latter against the ends of clutch jaws 21 when the nut 14 is tightened.

Fig. 1 illustrates how the drive cable 1%), 11 is fed between feed rolls 26 and 27, the former having a series of concave serrations 28 helically arranged for meshing engagement with the turns of the drive cable sections 10, 11 etc. The nut 14 has on its periphery a series of turns of a head 29 extending helically therearound and corresponding in pitch diameter and cross section to the outer walls of the turns of spring wire in the drive cable sections 10, 11. The turns of the head 29 are therefore adapted to mesh with the serrations 28 of the feed roller 26 as the nut passes between the feed rollers, thus providing for continued feeding of the drive cable from the apparatus with the coupling joints passing through the drive rollers without interrupting the feeding operain the drive cable section 10. On the turns of peripheral head 29 of nut 14, are a series of wrenching flats 30 which are arranged in hexagonal array as shown (or may be squared) to provide for wrenching of the nut 14 onto the threaded neck 18 of coupling part 12. For screwing the coupling part 13 into drive rod section 11, the wrench may be applied directly to the clutch jaw 24 or a spare coupling part 12 may be used as a wrench socket and may be wrenched by application of torque to its wrenching head 19. a

It will be understood that once the coupling parts 12 and 13 are installed in their respective drive cable sections, they will be left permanently anchored in the ends of those sections and that the coupling and uncoupling'of sections will be effected by operation of the nut 14 which will remain captive on the neck of coupling part 13.

As shown in Figs. 6, 7 and 8 instead of the rectangular clutch jaws 21 and 24, the respective coupling parts 12a and 13a may utilize a driving connection consisting of a radial driving finger 31 on the end of a stem 32, extending into an axially elongated radial slot 33 in the peripherally beaded nut portion 14:: of the coupling part 134 which in this case may have the nut portion 14a formed as an integral socket on one end of its shank portion 22.

The nut member 14a is threaded onto a threaded neck portion 17a of a collar 19a providing a hexagonal or squared head corresponding to the head 19 of coupling part 12, but separate from and rotatable on the stem 32 of the coupling part 12a. It has the helically beaded periphery the same as nut 14.

In Figs. 2 and 6, for improved clarity of illustration, the parts are shown partially assembled, i.e., they are not drawn together as tightly as they can be in the fully assembled, tightened coupling.

When the threaded neck 17a is drawn tightly and fully into the nut socket 14a, it will confine the finger 31 in the far end of the slot 33 to tighten the driving connection.

I claim:

1. In combination with a pair of flexible drive cable sections each having a tubular end portion in the form of a closed-coil helix, for use in connection with a drive rod feeding apparatus including a feed roll having a helically scalloped periphery for meshing engagement with the external walls of the turns of said helix; a pair of coupling parts each having a shank provided with a male helical thread meshing with the helical interior of a respective one of said tubular end portions and having opposed ends with respective jaw clutch parts for meshing engagement with one another; one of said coupling parts having a head defining an annular radial shoulder adjacent its respective shank; the other of said coupling parts having an externally threaded neck on its said opposed end; and a nut rotatably captive on said one coupling part and having a projecting internally threaded end portion for threaded connection with said neck, whereby to couple said coupling parts together with said jaw clutch parts in clutching interengagement; said nut having a helical bead in its periphery corresponding to the helical peripheries of said drive cable sections so as to mesh with said feeding roll. 7 V

2. A coupling for joining a pair of flexible drive cable sections each having a tubular end portion in the form of a closed-coil helix, for use in connection with a drive rod feeding apparatus including a feed roll having a helically scalloped periphery for meshing engagement with the external walls of the turns of said helix, said coupling comprising: a pair of coupling parts each having an externally threaded shank adapted to be threaded into a respective one of said tubular end portions, mating with the internal walls of the turns of said helix; one of said coupling parts having a cylindrical head and having jaw clutch means projecting from the end thereof, the other of said coupling parts having an externally threaded neck provided with jaw clutch means adapted to be coupled to said first mentioned jaw clutch means; and a nut rotatably mounted upon said one coupling part, retained by said cylindrical head and having an internal thread adapted to be threaded upon said externally threaded neck of the other coupling part for joining said coupling parts to one another; said nut having a helical bead in its periphery corresponding to the helical peripheries of said drive cable sections so as to mesh with said feed roll.

3. The combination defined in claim 2, wherein the jaw clutch means of said other coupling part comprises a pair of clutch jaws separated by a diametral slot in the end of said threaded neck and wherein the jaw clutch means of said one coupling part comprises a rectangular jaw extending diametrically of the end face of said cylindrical head and receivable in said slot.

4. The combination defined in claim 1 wherein said nut has a series of wrenching flats in the turns of said helical bead of its periphery.

5. In combination with a pair of flexible drive cable sections each having a tubular end portion in the form of a closed-coil helix, for use in connection with a drive rod feeding apparatus including a feed roll having a helically scalloped periphery for meshing engagement with the external walls of the turns of said helix; a pair of coupling parts each having a shank provided with a male helical thread for meshing with the helical internal Wall of a respective one of the opposed ends of said cable sections, said coupling parts having opposed ends provided with respective jaw clutch parts for meshing engagement with one another to provide a drive connection; an externally threaded neck member carried by one of said coupling parts in opposed relation to the other coupling part;

and an internally threaded nut member on said other coupling part, adapted for threaded coupling engagement with said externally threaded neck member for joining the coupling parts to one another and securing said drive 3 connection, said nut member having a helical bead in its periphery corresponding to the helical peripheries of said drive cable sections so as to mesh with said feeding roll. 6. A coupling as defined in claim 5, wherein said one coupling part has a stem projecting axially from its respective shank and a driving finger projecting radially from the end of said stem; wherein said externally threaded neck member constitutes one end portion of a collar loosely encircling and carried upon said axially projecting stem between said shank and said drive finger;

'and wherein said nut member is in the form of an internally threaded integral socket on one end of the shank of the other coupling part and is provided in one side thereof with an axially elongated radially projecting slot in which said drive finger is received with driving engagement with said nut member.

7. A coupling for joining sections of a flexible drive rod each having a tubu ar end in the form of a closed coil helix, adapted for longitudinal feeding engagement with a feed roll having a helically scalloped periphery for meshing engagement with the external surfaces of the turns of said helix, said coupling comprising: a pair of coupling parts each having a shank provided with a male helical thread for meshing with the helical interior of a respective one of said tubular end portions and having opposed ends with respective jaw clutch parts for meshing engagement with one another; one of said coupling parts having a head defining an annular radial shoulder adjacent its respective shank; the other of said coupling parts having an externally threaded neck on its said opof a closed-coil helix, for use in connection with a drive rod feeding apparatus including feed roll having a helically scalloped periphery for meshing engagement with the external Walls of the turns of said helix; a pair of coupling parts each having a shank secured in the end of a respective cable end portion, said coupling parts having opposed ends provided with respective jaw clutch parts for meshing engagement with one another to provide a drive connection; an externally threaded neck member carried by one of said coupling parts in opposed relation to the other coupling part; and an internally threaded nut member on said other coupling part adapted for References (Iited in the file of this patent UNITED STATES PATENTS 10 2,234,504 Robinson et al Mar. 11, 1941 2,278,324 Kollmann Mar. 31, 1942 2,297,167 Robinson et al Sept. 29, 1942 

